In Kelly Lambert's lab at the University of Richmond, rats are trained to drive tiny cars. Researchers are studying how that training, and the anticipation associated with it, affects their brains. University of Richmond hide caption

A robot roams through rows of grapes at Cornell AgriTech's Geneva vineyards to look for signs of diseased plants. Allison Usavage/Cornell University hide caption

Aboard the International Space Station, astronauts cut their hair using a pair of electrical sheers connected to a vacuum. NASA astronaut Frank Rubio says, "It's not a pretty haircut, for sure." Getty Images hide caption

Matter and its weird, opposite antimatter annihilate each other "in a blaze of glory," says Jessica Esquivel, an experimental particle physicist at Fermilab. PeteDraper/Getty Images hide caption

It's Short Wave's 5th birthday! To celebrate, we answer our 5-year-old listeners' science questions. NickS/Getty Images hide caption

The abstract nature of zero — that it is a number meant to represent an absence — makes the number trickier for our brains to process than other small numbers. Jose A. Bernat Bacete/Getty Images hide caption

The thick-billed parrot, the only living parrot species native to the U.S., once roamed from the American Southwest all the way south to Venezuela. Now, the only wild population remaining lives high in the pine forests of Mexico's Sierra Madre. Laura Vero/San Diego Zoo Wildlife Alliance hide caption

Squirrels are omnivores, eating nuts, fruit, small insects — and according to a study published in the Journal of Ethology — voles. Sonja Wild, UC Davis hide caption